PROJECT SUMMARY Research findings from the breast cancer and environment research program (BCERP) have implications for reducing breast cancer risk later in life for adolescent girls. Supported by the precautionary principle, risk reduction activities include reducing exposures to certain chemicals (e.g., BPA, PFOA) and maintaining a healthy weight through exercise and diet, particularly during pubertal development, a window of susceptibility. Research efforts are necessary to understand effective mechanisms for communicating risk reduction recommendations to parents/caregivers so they can learn about and engage in risk reduction activities. Pediatricians, pediatric nurses, nurse practitioners, and family physicians are health care providers who comprise a key audience who can reach parents/caregivers as well as adolescents with risk reduction recommendations. Using a transdisciplinary approach that includes a Scientific and Community Partner Advisory Board, this research aims to build on the previous translational and communication science research of the investigators. Specifically, this project will: 1) assess the efficacy of the BCERP toolkits tailored for health professionals through formative research with pediatric health care professionals and assess the knowledge and information provision preferences of parents/caregivers using focus group interviews; 2) based on pediatric health care professional and parent/caregiver feedback, adapt BCERP toolkit content into engaging, motivational education and training modules that can be delivered either in-person or via an online, immersive experience to PHCPs; and 3) test the preliminary efficacy and feasibility of the two delivery mechanisms with PHCPs. This research will provide evidence for the effectiveness of using PHCPs as advocates for the early adoption of breast cancer risk reduction activities for adolescent girls.